Yes, solrep, I found rutila, n. - a spade in another Latin online wordlist, as well as rutilus, adj = red, golden, auburn (rutila would be the feminine form of the adjective; rutilus the masculine.)
One thing to watch, though, if you want to continue using your sign-off is the case of the noun, rutila. If it is being seized, it needs to take the accusative case, which, assuming it's a regular feminine noun, would be rutilam.
So, carpe rutilam.
Actually, I rather like it as "seize the red". Goes well with my usual email sign-off of "Cheers".
Oh, and I'm no Latin scholar either, just a nitus-pickerus.